Project description:Global control of the tuberculosis (TB) epidemic is seriously threatened by increasing prevalence of drug resistant (DR) M. tuberculosis (MTB) isolates. Many genome-wide studies have identified DR-associated SNPs and investigated their role in DR mechanisms. However, DR in ~30% of isolates has no clear genetic basis. DR mechanisms related to variation in gene/protein expression are known, but not well-studied.
Project description:Monocyte miRNAs govern both protective and pathological responses during tuberculosis through their differential expression and emerged as potent target for biomarker discovery and host-directed therapeutics. Thus, our profound interest is to look at the miRNA profile of sorted monocytes across TB disease spectrum (drug-resistance TB (DR-TB), drug-sensitive TB (DS-TB) and latent TB) and healthy individuals (HC) to understand the underlying pathophysiology and their regulatory mechanism.
Project description:Extensively drug resistant tuberculosis (XDR-TB) showed many different characteristics including the extreme drug resistance versus the drug sensitive clinical isolates (DS-TB), to know better about the reasons we used the tuberculosis host cells named as THP-1 (one kind of the macrophage cells) to be infected by the XDR-TB and DS-TB.DS strain A36 and the XDR strain B42 and was typical and selected by our lab. Then the total RNA of infected or uninfected THP-1 cells was extract and purified for the analysis by the chip (22K Human Genome chip representing the 21522 ORF of human with the oligonucleotide probe of 70 mer from CapitalBio Corp., Beijing, China). The results reflected the different expressed genes involved in apoptosis, secreted cytokines and signal pathway and so on. Those results might indicate the how the XDR-TB cause the pathogenesis. In this study, the well grown THP-1 cells were separated and cultured in three ampoules. Cells in one ampoules were infected with XDR-TB strain of B42. Cells in another ampoules were infected with DS-TB strain of A36, with the cells in the third one were not infected and just treated with PBS as the control. Then the dual channel method was used for detecting the hybridization of B42 vs the control or A36 vs control. This work was repeated for three times.
Project description:Tuberculosis (TB) remains a deadly disease. The genetic diversity of Mycobacterium tuberculosis was neglected in the past, but is increasingly recognized as a determinant of immune responses and clinical outcomes of TB. However, how this bacterial diversity orchestrates immune responses to direct differences in TB severity remains unknown. We studied 681 patients with pulmonary TB and found that phylogenetically related M. tuberculosis isolates from cases with mild disease induced robust cytokine responses in macrophages. In contrast, isolates associated with severe TB cases failed to do so. Using representative isolates, we show that M. tuberculosis inducing a low cytokine response in macrophages also diminished activation of cytosolic surveillance systems, including cGAS and the inflammasome, suggesting a novel mechanism of immune escape. Isolates exhibiting this evasion strategy carried mutations in various components of the ESX-I secretion system. We conclude that host interactions with different M. tuberculosis strains results in variable TB severity.
2020-02-26 | GSE138580 | GEO
Project description:WGS of DR-TB isolates in Chennai, India
Project description:Extensively drug resistant tuberculosis (XDR-TB) showed many different characteristics including the extreme drug resistance versus the drug sensitive clinical isolates (DS-TB), to know better about the reasons we used the tuberculosis host cells named as THP-1 (one kind of the macrophage cells) to be infected by the XDR-TB and DS-TB.DS strain A36 and the XDR strain B42 and was typical and selected by our lab. Then the total RNA of infected or uninfected THP-1 cells was extract and purified for the analysis by the chip (22K Human Genome chip representing the 21522 ORF of human with the oligonucleotide probe of 70 mer from CapitalBio Corp., Beijing, China). The results reflected the different expressed genes involved in apoptosis, secreted cytokines and signal pathway and so on. Those results might indicate the how the XDR-TB cause the pathogenesis.
Project description:Multi-drug resistance and latent infection are two major issues in current tuberculosis (TB) control and management. Capreomycin is an important drug used for TB with multi-drug resistance. A recent study also indicates that this drug possesses unique bactericidal activity against non-replicating TB bacilli among known anti-TB drugs. Thus, there is an urgent need for investigating the full-spectrum action of capreomycin. Here we conduct the first microarray-based study on capreomycin using the high-resolution Affymetrix oligonucleotide GeneChip system. The results indicate that capreomycin primarily acts on the information pathways but it also significantly affects cell wall, cell processes, intermediate metabolism and respiration in Mycobacterium tuberculosis. This study not only transcriptionally validates the specific molecular target, 16S rRNA, but also discovers potential new targets of capreomycin, including genes operating at the DNA level, such as Rv0054 (ssb) and Rv3715c (recR), as well as genes involved in cell division like Rv3260c (whiB2). In addition, the nuo gene cluster and the ATP synthase gene cluster are repressed. Keywords: Drug-induced Differential gene expression analysis